FAQ · Wattage, temperature & technique
What is the 3-second rule in soldering?
Last verified 2026-08-09
The 3-second rule is a guideline to apply heat to a joint for no more than about three seconds before solder should be flowing. It exists to protect heat-sensitive components and PCB pads from damage — prolonged dwell time can lift pads, degrade nearby components or overheat plastic housings. If a joint isn't taking solder within a few seconds, the fix is usually more heat (higher temperature or larger tip contact area), not more time at the same temperature.
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